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71.
72.
Coronary artery spasm (CAS) rarely worsens from single-vessel to simultaneous multivessel CAS naturally, and simultaneous multivessel CAS leads to serious conditions such as cardiopulmonary arrest (CPA). A 77-year-old Japanese man who took medications for CAS was transferred to our hospital due to persistent chest pain. On arrival, his vital signs were stable, but his electrocardiogram (ECG) showed ST-segment elevation in leads II, III and aVF. Ventricular fibrillation developed suddenly. Although routine cardiopulmonary resuscitation (CPR) including intravenous administration of epinephrine was performed immediately, he could not be resuscitated. After initiation of percutaneous cardiopulmonary support (PCPS), there was a return of spontaneous circulation. His ECG showed exacerbation of myocardial ischemia with ST-segment elevation in leads I, II, III, aVL, aVF and V3–V6. Emergency coronary angiography revealed severe CAS of the right and left coronary arteries, which was relieved completely by intracoronary administration of nitrates. He was diagnosed with acute myocardial infarction due to simultaneous 3-vessel CAS that progressed over time. About 6 h after arrival, he developed hemodynamic instability and died. CAS worsened from single-vessel to simultaneous 3-vessel spasm, and intracoronary administration of nitrates was effective in relieving CAS, which was documented by the ECG and coronary angiogram. Since CAS can progress over time, nitrates must be administered immediately. When CAS leads to CPA, epinephrine may be ineffective in CPR because of its vasoconstrictive effect on coronary arteries; therefore, PCPS should be initiated, and intracoronary nitrates should be administered.  相似文献   
73.
To investigate the seroprevalence of severe fever with thrombocytopenia syndrome (SFTS) among wild and companion animals on Tsushima Island, Japan, SFTS virus (SFTSV)-specific ELISA and virus-neutralizing tests were conducted on 50 wild boars, 71 Sika deer, 84 dogs, 323 domestic cats, and 6 Tsushima leopard cats. In total, 1 wild boar (1.8%), 2 dogs (2.4%), 7 domestic cats (2.2%), and 1 Tsushima leopard cat (16.7%) were positive for anti-SFTSV antibodies. Among the 11 positive animals, 10 were collected after 2019, and all were found on the southern part of the island. SFTSV, thus far, seems to be circulating within a limited area of Tsushima Island. To protect humans and animals, including endangered Tsushima leopard cats, from SFTSV infection, countermeasures are needed to prevent the spread of SFTSV on Tsushima Island.  相似文献   
74.
The normal bone turnover is important for ESRD patients in not only skeletal problem but also patients QOL and survival. The abnormal bone turnover often induces the renal osteodystrophy and ectopic calcification. The major regulative factor on bone turnover is PTH. We propose here the target zone of PTH in ESRD patients with skeletal resistance for PTH. We recommended the intact-PTH 100 - 150 pg/mL for normal Ca/Pi/bone metabolism. This range of intact-PTH is equivalent to C-PTH 4.0 - 6.2 ng/mL, HS-PTH 10.0 - 16.0 ng/mL, and whole-PTH 80 - 110 pg/mL. The maintenance of normacalcemia and normophosphatemia are important for the arrival into the target zone of PTH using active vitamin D.  相似文献   
75.
Become almost non-existent in the developed countries, the hospital-borne tetanus always stays of current events in our country in spite of the forensic problem which it puts. The objectives of this study were to determine prevalence of this affection, to describe its clinical picture and to determine its lethality. It is about a retrospective study of a duration of 11 years realized in the service of the infectious diseases of Conakry. Among 8649 hospitalizations from 2001 till 2012 we brought together 239 cases of tetanus (2.7%) among which 60 hospital-borne tetanus (0.7%). Men represented 73% of these cases, with a sex-ratio M/F of 2.7. The age bracket of 20–40 years was the most affected with 32 cases (53.3%). A single patient had begun his vaccinal calendar which had remained incomplete. Both national hospitals of the CHU of Conakry and private hospitals were the biggest suppliers of this hospital-borne tetanus with respectively 22 and 27 cases (36.6 and 45%). Tetanus related to IM of quinine represented 26 cases (43.3%) whereas the hernial cure was found in 16 cases (26.6%). The average duration of invasion and incubation was respectively 1.5 days and 6 days for the dead (n = 45.7%) and 2 days and 10.5 days for the survivors. Three-quarters of 60 patients died. The fight against this type of tetanus passes inevitably by an improvement of the working conditions, a strict application of the rules of asepsis and the in-service training of the medical and paramedical staff.  相似文献   
76.
77.
Free d ‐serine (d ‐Ser) plays a crucial role in regulating brain function in mammals. In various organisms, including mammals, d ‐Ser is biosynthesized by Ser racemase, a synthetic enzyme that produces d ‐Ser from l ‐Ser. Ser racemase also exhibits dehydratase activity toward several hydroxyamino acids. Thus, this enzyme is unique in that it possesses the capability to both synthesize and degrade d ‐Ser; however, the physiological significance of its degradative activity remains unclear. In contrast to the physiological roles of d ‐Ser in mammals, little is known about the role of this amino acid in lower organisms, including the nematode Caenorhabditis elegans. It is known that a mammalian Ser racemase homologue (T01H8.2) from C. elegans exhibits racemase activity. Here, the enzymatic properties of recombinant T01H8.2 were characterized and compared with those of recombinant human Ser racemase. Furthermore, the levels of several d ‐ and l ‐amino acids were measured in wild‐type C. elegans and in a mutant in which the T01H8.2 gene is partially deleted and thereby inactivated. The results indicate that T01H8.2 also shows dehydratase activity toward several hydroxyamino acids, although the enzyme is not critical for Ser metabolism in vivo. The possible physiological roles of T01H8.2 are discussed.  相似文献   
78.
The effects of a short course of a COX-2 inhibitor on bone healing when the drug is discontinued are unknown. We examined the effects of rofecoxib on bone ingrowth over a 6-week period using a well-defined animal model. The Bone Harvest Chamber was implanted bilaterally in mature rabbits. After osseointegration of the chamber, the following treatments were given for 6 weeks each, followed by a harvest in each case: control-no drug; oral rofecoxib (12.5 mg/day) for the first 2 of 6 weeks; washout period-no drug; oral rofecoxib for the last 2 of 6 weeks; washout period-no drug; rofecoxib given continuously for all 6 weeks. Harvested specimens were snap-frozen, cut into serial 6-microm sections, and stained with hematoxylin and eosin and alkaline phosphatase (osteoblast marker), and processed using immunohistochemistry to identify the vitronectin receptor (osteoclast-like cells). Rofecoxib given continuously for 6 weeks yielded statistically less bone ingrowth compared to the control treatment. Rofecoxib given during the initial or final 2 weeks of a 6-week treatment did not appear to interfere with bone ingrowth. This suggests that the effects of COX-2 inhibitors on bone are less profound when the drug is administered for a short period of time.  相似文献   
79.
Although injury of epithelial cells has been reported to be responsible for renal disease such as acute renal failure, its molecular mechanisms are largely unknown. As hypoxia has been postulated as the initial trigger of epithelial injury, we studied the molecular mechanisms of apoptosis induced by hypoxia in human renal epithelial cells. Severe hypoxia caused epithelial cell death, accompanied by a significant increase in LDH release (p<0.01). In addition, hypoxic treatment of epithelial cells resulted in a significant increase in apoptotic cells as assessed by cell morphology (p<0.01). The apoptotic change in epithelial cells under hypoxic condition was also confirmed by a significant increase in caspase-3-like activity and release of cytochrome c (p<0.01). The decrease in epithelial cell number was completely abolished by addition of a wide-spectrum caspase inhibitor, Z-VAD, rather than Z-DEVD, a specific caspase-3 inhibitor (p<0.01). Thus, we further studied the molecular mechanisms of apoptosis induced by hypoxia. Anti-apoptotic factors, Bcl-2 and Bcl-xL, were significantly decreased in epithelial cells under a hypoxic condition as assessed by Western blotting (p<0.01). In contrast, hypoxia did not alter their location. Of particular importance, translocation of a proapoptotic factor, Bax, from the cytoplasm to the mitochondrial membrane was observed in response to hypoxia, whereas total Bax protein was not changed by hypoxia. Overall, this study demonstrated that hypoxia caused epithelial cell death induced by caspase-3-like activity-dependent apoptosis. The pro-apoptotic mechanisms of hypoxia in epithelial cells largely depend on a significant decrease in Bcl-2 and Bcl-xL. In addition, the present results demonstrate that translocation of Bax from the cytosol to the mitochondrial membrane occurred under hypoxia, thereby leading to pathological tissue destruction.  相似文献   
80.
The specificity of copromotion effects of caffeine with known goitrogenic factors on thyroid carcinogenesis was examined in rats pretreated with N-bis(2-hydroxypropyl)nitrosamine (DHPN). Male F344 rats were divided into 8 groups, each consisting of 10 animals, and received a single sc injection of 2,800 mg/kg DHPN. From one week after the DHPN initiation, they were given basal diet, iodine deficiency (ID) diet, 500 ppm phenobarbital (PB) solution or 1,000 ppm sulfadimethoxine (SDM) solution with or without 1,500 ppm caffeine feeding for 12 weeks. The caffeine, PB, SDM, and ID treatments significantly (p < 0.05 or 0.01) increased the relative thyroid weights, and the increases with PB or ID were further (p < 0.05 or 0.01) enhanced in combination with caffeine. SDM drastically promoted thyroid carcinogenesis in association with increased serum TSH levels regardless of the caffeine treatment. Thyroid follicular carcinomas and adenomas were more frequently observed in the additional caffeine groups than in the ID alone groups. The incidence and multiplicity of focal thyroid follicular hyperplasias in the ID-treated groups were significantly (p < 0.05 and 0.01) elevated in the case of combination with caffeine. Increases in serum TSH levels with PB or ID were also further enhanced in combination with caffeine. Serum thyroid hormone levels were significantly (p < 0.01) decreased by SDM but significantly (p < 0.05 or 0.01) increased by caffeine, PB or ID. Our results clearly indicate that dietary caffeine at a high dose of 1,500 ppm interacts with ID, but neither SDM nor PB, to promote rat thyroid carcinogenesis although the combined caffeine + PB treatment somewhat affected thyroid weights as well as thyroid hormone levels.  相似文献   
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